Small Craft Advisory 260, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
145 AM AKST Thu Nov 24 2016

.DISCUSSION...
The 00z model suite initialized well against the 00z analysis and
verified well against the 06z analysis. Model spread both between
model families and from run to run is minimal in the short range
but displays considerable spread over the weekend and continues to
display considerable spread into the long range.

Aloft at 500 hpa, a ridge currently over the eastern Bering Sea
and western Alaska will continue to slide to the south and east
and will be located over the southeast mainland and southern Yukon
Friday as a strong shortwave moving southeast from the eastern
Bering Sea Friday morning moves over the northeastern Gulf of
Alaska Friday afternoon. A 504 DAM low currently 100 nm west of
Banks Island with a trough stretching from the low southwest to
Prudhoe Bay and Kotzebue will continue to dig south and west and
deepen to 500 DAM as the low moves to around 150 nm north of the
McKenzie Delta Friday. The trough will continue to move south and
east into the interior and will be located along the Brooks Range
crest Friday afternoon and will push into the northern interior
Saturday morning.

Southwest flow ahead of the upper level trough will bring some
weak overrunning to much of the central and eastern interior
beginning Saturday and will continue into Monday. Low level winds
will turn more southerly Saturday afternoon and will cut off the
light snow with weak chinook flow over the middle and upper Tanana
Valley Saturday afternoon especially south and east of Fairbanks
however lifting with the overunning should prevail to the north
and west of Fairbanks where light snow accumulations in the 1 to 2
inch range will be possible Saturday into Monday. The upper level
trough over the western interior will shift north and west
slightly Monday and combined with a shortwave moving northeast in
the flow will allow the moist layer from the surface to 700 mb to
shift from southerly to southwestward on Monday allowing light
snow to move back into the middle Tanana Valley bringing a chance
of light snow to Fairbanks.

On Tuesday as the shortwave moves north and east low level winds
will shift to the north over the interior and will push a cold
airmass south over much of the interior. 850 mb temperatures
currently around 8 below over Fairbanks will drop to around 15
below Friday but then warm to around 10 below over the weekend and
drop again to around 15 below Monday. 850 mb temperatures drop to
below 20 below over Fairbanks beginning Tuesday of next week and
continue in the 20 to 25 below range for much of next week before
warming up again next weekend. With the cold airmass aloft over
much of northern Alaska, the temperatures realized at the surface
will again be highly dependent on local cloud over northern Alaska
into next week with significantly below normal temperatures
occuring where cloud cover is minimal and below normal
temperatures occuring where clouds prevail. Below normal
temperatures are expected through the period over the north slope
and will drop to below normal in the western interior as well as
the west coast of Alaska as the cold air filters to the south and
west early next week.

Coastal Hazard Potential Days 3 and 4...None.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Heavy Freezing Spray Warning for PKZ200-PKZ210-PKZ220-PKZ225-
PKZ230.

Small Craft Advisory for PKZ200-PKZ210-PKZ220-PKZ230.

Gale Warning for PKZ225.

Brisk Wind Advisory for PKZ215.
&&

CCC NOV 16